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121.
This paper presents a set of 128 halftone patterns on an 8 × 8 block size. The patterns have been designed to produce an acceptable gray-scale rendition when the halftone is seen from a distance and, at the same time, to allow comparisons to be made among the intensity values of individual pixels at a closer look. A Pascal program is also presented that produces halftones on an HP Laserjet+ laser printer, and sample halftones are shown. Finally, a method is proposed that prevents images digitized with a 4:3 aspect ratio from being distorted when halftones are printed at the usual 1:1 aspect ratio.  相似文献   
122.
Previous research has found that test takers can score above chance level on reading comprehension tests even when the passages are omitted. The present research investigated whether the effect would vary as a function of race. In Study 1, 386 participants completed a reading test with the passages omitted. General mental ability and race were significantly correlated with test performance. In Study 2, 827 job applicants completed the test as part of an entry-level selection battery. Eliminating items for which large race differences existed in Study 1 had no real effect on the size of the Black-White mean difference.  相似文献   
123.
Venezuela has experienced quite a rapid rate of change at mid century but has not been able to attain real economic development. Yet the desirability of progress is a commonly shared value, although there are important differences within the society; for example, in the ways in which work is conceived, or the degree to which the common Latin American values are ascribed. Besides, the concern with power, which is also identified as important within Venezuelan society and often gets combined with the socio-centric values into ‘political partisanship’, is a factor affecting organizational functioning, particularly in the public sector. Examples are given of unsuccessful and successful organizations, pointing out the need to take into account the commonalities and diversities in values identified within the society in the search of organizational alternatives more viable within the particular context.  相似文献   
124.
The relationship between hyperactivity and neuropsychological test performance at different age levels was examined. It was found that for young children (6 to 8 years of age, n=90), there was no significant association between hyperactivity/attentional problems (as measured by the Hyperactivity scale of the Child Behavior Checklist) and performance on neuropsychological tasks thought to contain an attentional component (WISC-R Coding, Arithmetic, and Digit Span; WRAT Arithmetic; and the Benton Visual Retention Test). However, for older children (9 to 12 years of age, n=92), there were significant and large negative correlations between CBC Hyperactivity scores and Coding, WRAT Arithmetic, and Benton VRT scores. Multiple regression analyses supported the above results (for Coding and WRAT Arithmetic), indicating that hyperactivity/inattention has a particularly deleterious effect on test performance (relative to sameage peers) as age increases.Aspects of the research reported in this article were presented at the 1987 meeting of the International Neuropsychological Society in Washington, D.C. The authors gratefully acknowledge the assistance of William Ingram and Lisa Rosa in the data collection.  相似文献   
125.
Science and Engineering Ethics - Synthetic biology opens up the possibility of producing new entities not found in nature, whose classification as organisms or machines has been debated. In this...  相似文献   
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128.
Cultural illiteracy and the Internet.   总被引:1,自引:0,他引:1  
The Internet has created different expectations regarding its possibilities as a tool for including groups that have heretofore been excluded from the modern world. But mere access to information does not necessarily imply correct and effective use of it. Despite the great increase in Internet access in previously excluded areas, expectations of inclusion have not been fulfilled. Research suggests that the effectiveness of Internet use varies among cultures, but all such studies analyze countries as a whole with no further breakdown. Yet it is known that within a given country there co-exist subcultures that differ both in language and social context. This paper presents a study that shows the correlation between different social subcultures and their Internet knowledge.  相似文献   
129.
A review of research on prenatal depression effects on the fetus and newborn suggests that they experience prenatal, perinatal and postnatal complications. Fetal activity is elevated, prenatal growth is delayed, and prematurity and low birthweight occur more often. Newborns of depressed mothers then show a biochemical/physiological profile that mimics their mothers' prenatal biochemical/physiological profile including elevated cortisol, lower levels of dopamine and serotonin, greater relative right frontal EEG activation and lower vagal tone. Elevated prenatal maternal cortisol is the strongest predictor of these neonatal outcomes. Moderate pressure massage can alleviate these effects including reducing prematurity.  相似文献   
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